I'd be interested, and willing to pay a reasonable price for such an item. Hauling my laptop in a backpack with a cord wrapped all over the place is a pain in the ass.
Here's a feature that would be very convenient and useful:
Plug the device into the diagnostic connector, and leave it there. Whenever the key is on, it is recording, say up to an hour. At that point it would stop recording and hold whatever data it captured. Turn the key off, the data is saved. Once the key is turned back on again, the data is erased or overwritten.
This would be very useful, as we could simply leave the device plugged in at all times, and if a problem arose with the bike, we would have instant data to help diagnose the issue.
Or if the device is being used for tuning, just plugging it in and riding, without having to worry about hitting a "record" button would rock.
I look forward to what you come up with!
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